This invention relates to industrial robots, and more particularly to a robot of the kind comprising a movable arm, a wrist pivotally mounted on the arm and an end shaft carried by the wrist.
When such a robot is used for holding a component having to be subjected to operations such as polishing or grinding operations, it is essential for the robot to keep the component as still as possible. This is generally achieved by resorting to electric motors having a large positioning torque. Such an arrangement suffers however from the dual drawback of not ensuring absolute immobility and more importantly of requiring a heavier motor, thereby substantially slowing down the movements of the robot. This dual drawback is particularly bothersome with small robots whose speed, at least as regards the wrist and the end shaft, is precisely one of its major attributes.